The present invention relates to a method and facility for removing sludge from water, and includes the steps of separating the inorganic constituents or matter in the sludge, such as stones, gravel, etc., from the organic matter, such as wood, roots, etc. The method and facility are also suitable for processing sediment that contains decaying organisms.
Sludge that is removed from water contains a number of constituents that can be divided approximately into inorganic and organic constituents. The inorganic constituents are primarily stones, gravel, sand, etc., while the organic constituents include wood and roots. The organic constituents also include oils that have been introduced into the water and have contaminated the latter. The sludge furthermore includes chemical contaminants, such as phosphates that have been introduced into the water and have become dissolved therein.
The objective of removing sludge from water is to rid the water of these inorganic and organic constituents. Actually, the greater problem arises as to what to do with this matter after it has been removed from the water. Since dumps are becoming continuously more scarce, a further objective during the removal of sludge from water must be the recovery of inorganic and organic constituents, such as stone, gravel, sand, wood, roots, etc., and the subsequent use of such matter as economically usable material. It should be necessary to place only a fraction of this matter in dumps. However, with the heretofore known methods and facilities, this objective cannot be achieved in a fully satisfactory manner, so that a large portion of sludge removed from water still has to be placed in dumps.
It is therefore an object of the present invention to improve the heretofore known methods and apparatus for removing sludge from water in such a way that small quantities only have to be placed in dumps, and that the rest of the constituents of the sludge can be provided for subsequent use as economically usable material.